Re: [PATCH V2 4/5] drivers/rtc/rtc-ds1307.c: Support optional wakeup interrupt source

From: Grygorii Strashko
Date: Wed Jun 24 2015 - 11:37:48 EST


On 06/23/2015 07:15 PM, Nishanth Menon wrote:
With the recent pinctrl-single changes, SoCs such as Texas
Instrument's OMAP processors can treat wake-up events from deeper idle
states as interrupts.

Let's add support for the optional second interrupt for wake-up using
the generic wakeirq support added in commit 4990d4fe327b ("PM /
Wakeirq: Add automated device wake IRQ handling")

Finally, to pass the wake-up interrupt in the dts file,
interrupts-extended property needs to be passed.

This is similar in approach to commit 2a0b965cfb6e ("serial: omap: Add
support for optional wake-up") + ee83bd3b6483 ("serial: omap: Switch
wake-up interrupt to generic wakeirq")

Signed-off-by: Nishanth Menon <nm@xxxxxx>
---
Changes since V1:
- dropped the need for specific suspend-resume handlers generic api
has adequate hooks for those
- little more code flow cleanups.

V1: https://patchwork.kernel.org/patch/4759171/

drivers/rtc/rtc-ds1307.c | 41 ++++++++++++++++++++++++++++++++++++++---
1 file changed, 38 insertions(+), 3 deletions(-)

diff --git a/drivers/rtc/rtc-ds1307.c b/drivers/rtc/rtc-ds1307.c
index b03880fc32b5..b00d97dbf955 100644
--- a/drivers/rtc/rtc-ds1307.c
+++ b/drivers/rtc/rtc-ds1307.c
@@ -15,6 +15,9 @@
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/pm_wakeirq.h>
#include <linux/rtc/ds1307.h>
#include <linux/rtc.h>
#include <linux/slab.h>
@@ -114,6 +117,7 @@ struct ds1307 {
#define HAS_ALARM 1 /* bit 1 == irq claimed */
struct i2c_client *client;
struct rtc_device *rtc;
+ int wakeirq;
s32 (*read_block_data)(const struct i2c_client *client, u8 command,
u8 length, u8 *values);
s32 (*write_block_data)(const struct i2c_client *client, u8 command,
@@ -1156,6 +1160,8 @@ read_rtc:
}

if (want_irq) {
+ struct device_node *node = client->dev.of_node;
+
err = devm_request_threaded_irq(&client->dev,
client->irq, NULL, irq_handler,
IRQF_SHARED | IRQF_ONESHOT,
@@ -1163,13 +1169,36 @@ read_rtc:
if (err) {
client->irq = 0;
dev_err(&client->dev, "unable to request IRQ!\n");
- } else {
+ goto no_irq;
+ }
+
+ set_bit(HAS_ALARM, &ds1307->flags);
+ dev_dbg(&client->dev, "got IRQ %d\n", client->irq);

- set_bit(HAS_ALARM, &ds1307->flags);
- dev_dbg(&client->dev, "got IRQ %d\n", client->irq);
+ /* Currently supported by OF code only! */
+ if (!node)
+ goto no_irq;
+
+ ds1307->wakeirq = of_irq_get(node, 1);
+ if (ds1307->wakeirq <= 0) {
+ if (ds1307->wakeirq == -EPROBE_DEFER) {
+ err = ds1307->wakeirq;
+ goto exit;
+ }
+ ds1307->wakeirq = 0;
+ goto no_irq;
+ }

Might be above code could be done a little bit simpler?

err = of_irq_get(node, 1);
if (err <= 0) {
if (err == -EPROBE_DEFER)
goto exit;
goto no_irq;
}
ds1307->wakeirq = err;

+
+ err = dev_pm_set_dedicated_wake_irq(&client->dev,
+ ds1307->wakeirq);
+ if (err) {
+ dev_err(&client->dev, "unable to setup wakeIRQ %d\n",
+ err);
+ goto exit;
}
}

+no_irq:
if (chip->nvram_size) {

ds1307->nvram = devm_kzalloc(&client->dev,
@@ -1206,6 +1235,9 @@ read_rtc:
return 0;

exit:
+ if (ds1307->wakeirq)
+ dev_pm_clear_wake_irq(&client->dev);
+
return err;
}

@@ -1213,6 +1245,9 @@ static int ds1307_remove(struct i2c_client *client)
{
struct ds1307 *ds1307 = i2c_get_clientdata(client);

+ if (ds1307->wakeirq)
+ dev_pm_clear_wake_irq(&client->dev);
+
if (test_and_clear_bit(HAS_NVRAM, &ds1307->flags))
sysfs_remove_bin_file(&client->dev.kobj, ds1307->nvram);




--
regards,
-grygorii
--
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